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MYSQL-GENOCIDE(1) User Contributed Perl Documentation MYSQL-GENOCIDE(1)

NAME
mysql-genocide - Parallel operation on MySQL processlist

SYNOPSIS
mysql-genocide [OPTIONS] [FILTER]

Options:
-h, --help Show help.

Connection:
-h, --host=name Connect to host.
-P, --port=# Port number to use for connection.
-D, --database=name Database to use.
-u, --user=name User for login if not current user.
-p, --password=name Password to use when connecting to server.

Filters:
-e, --exclude Exclude queries by different criteria
-s, --selects-only Exclude everything but selects
-t, --min-time=# Exclude queries with exec time lower than #
-T, --timeout Exclude queries with exec time lower than query time hint
-l, --limit=# Only take first # lines
-g, --placeholder Replace values in queries by placeholders
-d, --distinct Only keep the first occurence of the same query
--sort Sort result

Actions:
-L, --list Output list of queries
-K, --kill Kill every matched threads
-S, --stats Show some stats about processlist

-i, --interval[=#] Repeat the command at regular interval

OPTIONS
--help
Print a brief help message and exits.

--host, --port, --database, --user, --password
See mysql cli help for more information on those parameters.

--exclude=[!]name
Exclude from the running thread list queries matching the argument.
This parameter can be repeated several times to exclude different
kinds of queries. If you prefix the argument with an exclamation
mark (!), all thread not matching this argument will be excluded.
Allowed parameters are:

select, insert, replace, update, delete, create, drop, alter

Exclude SQL query which command is of the same name.

write

Exclude every SQL query doing write operation (insert, replace,
update, delete).

other

Exclude SQL query which are none of the above type.

sleep

Exclude all sleeping threads

system

Exclude thread ran by the system (often used for replication
threads)

user=<user>

Exclude threads ran by given mysql username.

db=<db>

Exclude threads using given database.

state=<state>

Exclude threads in given state.

See
<http://dev.mysql.com/doc/refman/5.0/en/general-thread-states.html>
for the list of possible states

command=<command>

Exclude threads using given command.

See <http://dev.mysql.com/doc/refman/5.0/en/thread-commands.html>
for the list of possible commands.

--selects-only
This is equivalent to: --exclude=write --exclude=other
--exclude=sleep --exclude=system.

--min-time=#
Exclude queries with execution time lower than given parameter.

--timeout
Keep only queries with a timeout provided and with an execution
time which exceeded this timeout. The timeout can be provided with
the query in a comment like this:

SELECT /* timeout:40 */ * FROM table;

Timeout is expressed in second.

--limit=#
Take first # threads and excludes others.

--placeholder
Will try to make queries more generic by replacing all values by
either "i" for numbers or "s" for strings.

--distinct
Keep only the first query from group of identical queries and
exlude others.

Note: If you use this option with --placeholder, queries that would
differ only by values used will become identical. This is useful to
distinct big type of queries.

--sort[=name]
Sort matched queries by parameter given as argument.

Allowed parameters are as follow:

concurrency or c

Sort queries by most repeated ones.

time or t

Sort queries by longer execution time.

--list[=template]
Output the result to the terminal.

The default output format can be changed by supplying a template
with desired field.

Available fields are: Id, User, Command, State, Db, Host, Time,
Info, Group, Concurrency, QType, Timeout

Default template is: <Id> <User> <Db> <Time> <Info>

--kill
Kill every threads that match the given filters.

--stats
Show statistics about queries matched by filters.

--interval[=#]
Repeat the command at regular interval. Interval in second can be
specified as argument. If not specified, default interval is 5
seconds.

DESCRIPTION
mysql-genocide helps you play with big MySQL processlists. It can
filter it using different criterias like execution time, query type,
user or regexp matching of the SQL query etc. Actions can then be
peformed on the result like killing, sorting or generating statistics.

EXAMPLES
Kill all selects with execution time geater than 60 seconds:

mysql-genocide --selects-only --min-time 60 --kill

Same as before but limited on queries matching a pattern:

mysql-genocide -s -t 60 -K 'FROM user '

Kill all queries timed out:

mysql-genocide --timeout --kill

Replace queries values by placeholders and group identical queries
together, sort them by most concurrent and keep only the 10 most
concurent ones:

mysql-genocide --placeholder --group --sort concurrency --limit 10 --list

SQL EXTENDED INFO
You can add some information in your SQL queries to help mysql-genocide
to do some decisions. To pass this kind of information, you can use SQL
comments like this:

/* VARIABLE[:VALUE] */ SELECT * FROM...

NOTE: in certain versions of mysql CLI client strip comments before to
send them to the server.

AVAILABLE EXTENDED INFO

TIMEOUT:SECONDS
This option hint "mysql-genocide" on the maximum execution time the
query should take. The option --timeout will keep only queries with
an execution time which exceeded this value.

The timeout can be provided with the query in a comment like this:

/* timeout:40 */ SELECT * FROM table;

Timeout is expressed in second.

DO_NOT_KILL
If this option is present in query, the query won't be killed when
--kill option is used, even if it match the filters. If you combine
--list and --kill on the same command, such queries will appear in
the listed queries but won't be killed.

Example query:

/* DO_NOT_KILL */ SELECT * FROM important_data;

SCRIPT CATEGORIES
Unix/System_administration

PREREQUISITES
This script requires the "DBD::mysql", "Getopt::Long" and "Pod::Usage"
modules.

OSNAMES
any

AUTHOR
Olivier Poitrey <rs@dailymotion.com>

perl v5.20.2 2008-06-14 MYSQL-GENOCIDE(1)